app/assets/stylesheets/spree/backend/shared/_forms.scss in spree_backend-2.3.1 vs app/assets/stylesheets/spree/backend/shared/_forms.scss in spree_backend-2.3.2

@@ -30,9 +30,48 @@
 
 .fullwidth {
   width: 100%;
 }
 
+.input-group {
+  position: relative;
+  display: table;
+  border-collapse: separate;
+
+  .form-control,
+  .input-group-addon {
+    display: table-cell;
+
+    &:first-child {
+      border-top-right-radius: 0;
+      border-bottom-right-radius: 0;
+    }
+    &:last-child {
+      border-top-left-radius: 0;
+      border-bottom-left-radius: 0;
+    }
+  }
+
+  .form-control {
+    width: 100%;
+  }
+
+  .input-group-addon {
+    padding: 6px 10px;
+    border: 1px solid #cee1f4;
+    background: #eff5fc;
+    border-radius: 3px;
+
+    &:first-child {
+      border-right: none;
+    }
+
+    &:last-child {
+      border-left: none;
+    }
+  }
+}
+
 label {
   font-weight: 600;
   text-transform: uppercase;
   font-size: 85%;
   display: inline;